2016 siesta brake and turn signal not working

I have spent the better part of the day in the phone with Thor and Mercedes with a problem.
The brake lights and turn signals on the rear of the motor home are not working. The turn signals are working on the front of the van.
No one knows where there might be a fuse that I could check or any idea how to help

Our motor home has 7,000 miles on it and it a little over a year old.
Anywhere are in the road on a month long trip up the pacific coast. We are many miles away from Mercedes service center. Thor has been of little help.

Any ideas on how I might be able to get going safely again would be appreciated.


2015 Thor Siesta 24SR
Check the wiring by the grey water tank,and inside the rear bumper. There are a couple of plugs that might not have been pushed together very well. Also there could be cut wires, Thor did not do a very good job of dressing the wires on my Siesta
I took the motor home to a mechanic and he called Thor. They told him there I a 15 amp fuse under the drivers seat. So, $200 later the fuse was replaced.
Pretty crazy design. He replaced
The fuse with a 15 amp circuit breaker. This way if it happens again it will automatically reset.

I wonder what else is under the seat that would be good to know?


New member
I know this an old post but just got back from a three month trip in our Siesta and had the same problem. Actually there are two 15 amp fuses under the driver's seat that both are in light circuits and several relays. The fuses are in red fuse holders that look like after market. I had a short in my toad hook up wiring that blew my fuses. After the second time I found out the cause and corrected it. There was enough slack in the fuse holder wiring to be able to pull them out side the set, next the regular fuse panel on the side of the seat. Now I can change the fuses if need be without removing the seat. I would suggest that you remove the seat and looks at what's under there for future reference. Its not hard to do, only 4 bolts hold it down to the frame.


2016 Thor Siesta 24ST
Thank you for posting the issue and solution guys. I had the same problem with the brake and turn signal lights. One of the two 15A fuses was blown as described in this thread. To facilitate future fuse replacement, I moved the two existing fuse blocks under the drivers seat to the lower positions, and fasten the three non OEM fuse holders above the fuse blocks with tie wraps for easy access. (Attached picture was inverted during file upload)


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